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Fencer Intel
medium 6.0

CVE-2009-4444 json

Microsoft Internet Information Services (IIS) 5.x and 6.x uses only the portion of a filename before a ; (semicolon) character to determine…

published 16y ago modified 4mo ago also EUVD-2009-4411

cvss
6.0
version 2.0, NVD
cisa kev
Not listed
not in CISA's catalog
epss
63.6%
EPSS 63.6% chance of exploitation in 30 days, percentile 99.2%
public exploits
0
none known

Summary

Microsoft Internet Information Services (IIS) 5.x and 6.x uses only the portion of a filename before a ; (semicolon) character to determine the file extension, which allows remote attackers to bypass intended extension restrictions of third-party upload applications via a filename with a (1) .asp, (2) .cer, or (3) .asa first extension, followed by a semicolon and a safe extension, as demonstrated by the use of asp.dll to handle a .asp;.jpg file.

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Exploit prediction

63.63% chance of exploitation in the next 30 days, higher than 99.2% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 2.0 6.0 AV:N/AC:M/Au:S/C:P/I:P/A:P

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.